Perforator territory infarction in the lenticulostriate arterial territory: mechanisms and lesion patterns based on the axial location

Background: We hypothesized that perforator territory infarcts in the lenticulostriate territory (pLSAIs) may have heterogeneous lesion patterns and stroke mechanisms.

Methods: We reviewed prospectively collected patients who developed pLSAIs within 72 h after stroke onset. Lesion patterns were analyzed based on the six axial levels. Based on MR angiography, stenosis of the middle cerebral artery (MCA) was classified into 3 groups. White matter hyperintensities were assessed by Fazeka's scale of periventricular hyperintensity (PVH) and deep white matter hyperintensity (DWMH).

Results: Of 221 patients, 159 were normal, 44 had mild stenosis, and 18 had severe stenosis of the MCA. Larger infarct volume was correlated with the severity of MCA disease (r=0.289, p<0.001). Lower lesion patterns were correlated with the severity of MCA disease (r=-0.294, p<0.001). A higher lesion pattern was correlated with the severity of DWMH or PVH scores (r=0.205, p=0.002 in DWMH, and r=0.137, p=0.042 in PVH).

Conclusions: Patients with MCA disease have larger and lower lesion patterns beginning from the proximal territory of the lenticulostriate artery (LSA). Patients with severe white matter changes have smaller and higher lesion patterns in the distal territory of the LSA.